Comparison of steam pretreatment of eucalyptus, aspen, and spruce wood chips and their enzymatic hydrolysis

1992 ◽  
Vol 34-35 (1) ◽  
pp. 37-48 ◽  
Author(s):  
L. P. Ramos ◽  
C. Breuil ◽  
J. N. Saddler
Keyword(s):  
Enzymatic Hydrolysis ◽  
Wood Chips ◽  
Steam Pretreatment ◽  
Spruce Wood

scholarly journals Improvement of Enzymatic Saccharification of Cellulose-Containing Raw Materials Using Aspergillus niger

Processes ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 1360
Author(s):  
Ekaterina Budenkova ◽  
Stanislav Sukhikh ◽  
Svetlana Ivanova ◽  
Olga Babich ◽  
Vyacheslav Dolganyuk ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Aspergillus Niger ◽  
Filter Paper ◽  
Raw Materials ◽  
Enzymatic Saccharification ◽  
Wood Chip ◽  
Cellulase Activity ◽  
Wood Chips ◽  
Acid Pretreatment ◽  
Hydrolysis Of

Enzymatic hydrolysis of cellulose-containing raw materials, using Aspergillus niger, were studied. Filter paper, secondary cellulose-containing or starch-containing raw materials, miscanthus cellulose after alkaline or acid pretreatment, and wood chip cellulose, were used as substrates. The study focused on a wild A. niger strain, treated, or not (control), by ultraviolet (UV) irradiations for 45, 60, or 120 min (UV45, UV60, or UV120), or by UV irradiation for 120 min followed by a chemical treatment with NaN3 + ItBr for 30 min or 80 min (UV120 + CH30 or UV120 + CH80). A mixture of all the A. niger strains (MIX) was also tested. A citrate buffer, at 50 mM, wasthe most suitable for enzymatic hydrolysis. As the UV exposure time increased to 2 h, the cellulase activity of the surviving culturewas increased (r = 0.706; p < 0.05). The enzymatic activities of the obtained strains, towards miscanthus cellulose, wood chips, and filter paper, were inferior to those obtained with commercial enzymes (8.6 versus 9.1 IU), in some cases. Under stationary hydrolysis at 37 °C, pH = 4.7, the enzymatic activity of A. niger UV120 + CH30 was 24.9 IU. The enzymatic hydrolysis of secondary raw materials, using treated A. niger strains, was themost effective at 37 °C. Similarly, the most effective treatment of miscanthus cellulose and wood chips occurred at 50 °C. The maximum conversion of cellulose to glucose was observed using miscanthus cellulose (with alkaline pretreatment), and the minimum conversion was observed when using wood chips. The greatest value of cellulase activity was evidenced in the starch-containing raw materials, indicating that A. niger can ferment not only through cellulase activity, but also via an amylolytic one.

Combined Steam Pretreatment and Enzymatic Hydrolysis of Starch-Free Wheat Fibers

2004 ◽  
Vol 115 (1-3) ◽  
pp. 0989-1002 ◽  
Author(s):  
Beatriz Palmarola-Adrados ◽  
Mats Galbe ◽  
Guido Zacchi
Keyword(s):  
Enzymatic Hydrolysis ◽  
Steam Pretreatment ◽  
Hydrolysis Of

Optimization of steam pretreatment conditions for enzymatic hydrolysis of poplar wood

Holzforschung ◽  
2011 ◽  
Vol 65 (4) ◽  
Author(s):  
Fokko Schütt ◽  
Jürgen Puls ◽  
Bodo Saake
Keyword(s):  
Enzymatic Hydrolysis ◽  
Raw Material ◽  
Steam Pretreatment ◽  
Alkaline Extraction ◽  
Poplar Wood ◽  
Steam Refining ◽  
Severity Factor ◽  
Short Rotation ◽  
Pretreatment Conditions ◽  
Hydrolysis Of

Abstract Steam refining was investigated as a pretreatment for enzymatic hydrolysis of poplar wood from a short rotation plantation. The experiments were carried out without debarking to use an economically realistic raw material. Steam refining conditions were varied in the range of 3–30 min and 170–220°C, according to a factorial design created with the software JMP from SAS Institute Inc., Cary, NC, USA. Predicted steaming conditions for highest glucose and xylose yields after enzymatic hydrolysis were at 210°C and 15 min. Control tests under the optimized conditions verified the predicted results. Further pretreatments without bark showed that the enzymes were not significantly inhibited by the bark. The yield of glucose and xylose was 61.9% of theoretical for the experiments with the whole raw material, whereas the yield for the experiments without bark was 63.6%. Alkaline extraction of lignin from the fibers before enzymatic hydrolysis resulted in an increase of glucose yields from mild pretreated fibers and a decrease for severe pretreated fibers. The extracted lignin had a high content of xylose of up to 14% after very mild pretreatments. On the other hand, molecular weights of the extracted lignin increased substantially after pretreatments with a severity factor above 4. Hence, alkaline extraction of the lignin seems only attractive in a narrow range of steaming conditions.

Enhancement of ethanol production from spruce wood chips by ionic liquid pretreatment

2013 ◽  
Vol 102 ◽  
pp. 163-169 ◽  
Author(s):  
Marzieh Shafiei ◽  
Hamid Zilouei ◽  
Akram Zamani ◽  
Mohammad J. Taherzadeh ◽  
Keikhosro Karimi
Keyword(s):  
Ionic Liquid ◽  
Ethanol Production ◽  
Wood Chips ◽  
Ionic Liquid Pretreatment ◽  
Spruce Wood

Chemical and thermal properties of precipitates made from hydrolysate of spruce wood chips

2019 ◽  
Vol 53 (4) ◽  
pp. 889-909 ◽  
Author(s):  
Dmitry Tarasov ◽  
Mathew Leitch ◽  
Pedram Fatehi
Keyword(s):  
Thermal Properties ◽  
Wood Chips ◽  
Spruce Wood

Degradation of Poplar and Spruce Wood Chips Using Alkaline Glycerol

2005 ◽  
Vol 27 (11) ◽  
pp. 1073-1084 ◽  
Author(s):  
Ayhan Demirbaş ◽  
Ali Celik
Keyword(s):  
Wood Chips ◽  
Spruce Wood

A STUDY CONCERNING THE KINETICS OF THE SULPHITE PROCESS

1936 ◽  
Vol 14b (9) ◽  
pp. 336-345
Author(s):  
A. J. Corey ◽  
O. Maass
Keyword(s):  
Wood Chips ◽  
Wood Meal ◽  
Spruce Wood ◽  
Controlled Conditions ◽  
Kinetics Of

Delignification rates of spruce wood chips and wood-meal have been investigated under carefully controlled conditions at temperatures ranging from 100° to 140 °C. The rates are shown to be in only approximate agreement with the monomolecular law, but the change in the rate of delignification with temperature obeys the equation of Arrhenius.

Biomechanical pulping of spruce wood chips with Streptomyces cyaneus CECT 3335 and handsheet characterization

Holzforschung ◽  
2005 ◽  
Vol 59 (2) ◽  
pp. 173-177 ◽  
Author(s):  
Manuel Hernández ◽  
M. Jesus Hernández-Coronado ◽  
M. Isabel Pérez ◽  
Esteban Revilla ◽  
Juan C. Villar ◽  
...  
Keyword(s):  
Lignin Content ◽  
Middle Lamella ◽  
Treated Wood ◽  
Strength Properties ◽  
Wood Chips ◽  
Fiber Network ◽  
Spruce Wood ◽  
Gradual Loss ◽  
Acid Soluble Lignin ◽  
Streptomyces Cyaneus

AbstractThe actinobacteriumStreptomyces cyaneusCECT 3335 was evaluated for its ability to delignify spruce wood chips (Picea abies) after 2 weeks of incubation prior to refiner mechanical pulping. Weight loss of the chips during the treatment ranged from 2% to 3%. Chemicalanalysis of the treated wood showed an increase in acid-soluble lignin content concomitant with a notable increase in the acid/aldehyde+ketone [AC/(AL+KE)] ratio of the lignin compared with the control. Structural alterations in wood cell walls were observed by optical and scanning microscopy using astra blue-safranin staining and cryosections stained with gold/palladium, respectively. A gradual loss of lignin from the lumen towards the middle lamella and incipient defiberization could be observed. The estimation of specific energy for the defibration and refining stages of treated pulp showed a 24% reduction in the energy required, largely due to a 30% saving in the defibration of chips. The analysis of handsheets obtained from treated pulp showed a notable improvement in some strength properties, such as breaking length, tear index and stretch. In addition, the high Gurley air resistance value indicates more packing of the voids of the fiber network. These results demonstrate for the first time the suitability ofStreptomyces cyaneusfor biomechanical pulping purposes.

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